ObjectiveTo assess the effect of PM2.5 on sympathetic innervation and the relationship with cardiac nerve growth factor in healthy rat hearts,identify the ability to the sympathetic nerve reconstruction,and explore the possible arrhythogenic mechanism of PM2.5.MethodsForty healthy SD rats were instilled into trachea with two different solutions twice per week for four weeks:control group with saline and experimental group with PM2.5 25 mg/kg.Then these rats were killed,and biatrial appendages,two ventricular anterior walls were left.Immune cytochemical staining of cardiac nerves was performed using anti-tyrosine hydroxylase antibodies and cardiac nerve growth factor was detected by western blotting.ResuitsCompared with the control group,both the density of sympathetic nerves and the expression of cardiac NGF protein in the experimental group were much higher in the left ventricular anterior wall ( P＜0.01 and P＜0.05) and in the right ventricular anterior wall ( P＜0.01 and P＜0.05).ConclusionsPM2.5 can induce regional sympathetic hyperinnervation in both ventricular anterior walls in healthy rats by stimulating the NGF protein secretion,and the sympathetic nerve reconstruction effect of PM2.5 was confirmed.

Objective To investigate the accuracy of careful clinical evaluation in hemodynamic status and guidance of PiCCO monitor in clinical treatment.Methods A total of 96 hemodynamic unstable cases were evaluated prior to the insertion of the PiCCO catheter.The attending physician in charge of the patient was required to complete a questionnaire to predict the range of key hemodynamic variables for CI,GEDI,SVRI and EVLWI.Additionally,the attending was also asked to indicate a plan for therapy based on the predicted hemodynamic profile and decide if the predicted therapy plan was altered after the the first measurement of hemodynamic variables.Results The accurate prediction of hemodynamic variables was CI (55.2％),GEDI(60.4％),SVRI(63.5％) 和 EVLWI (78.1％),among which EVLWI had a higher accuracy(P ＜ 0.05).49％ doctors altered their planned therapy according to the result of the PiCCO information.Doctors had more difficulty in accurately predicting hemodynamic values in critical patients which APACHE Ⅱ scored 15 ～25 (42.3％ vs 67.9％ and 42.3 ％ vs 75.0％,x2 =4.755,5.231,P ＜ 0.05).The prediction of patients with acute myocardial infarction was more accurate than those of without acute myocardial infarction,and less to alter the planned therapy(21.1％ vs 55.8％,x2 =7.382,P =0.007).The patients of impaired oxygenation had less accurate predictions and less therapy alterations(32.3％ vs 56.9％,x2 =5.110,P =0.024).Attending was able to predict the hemodynamic status more accurately(63.9％ vs 40％,x2 =5.152,P =0.023) and alter the predicted therapy less(39.3％ vs 65.7％,x2 =6.189,P =0.013) in patients who were enrolled later.Conclusions Clinical evaluation in hemodynamic status of critically ill patients had a lower accuracy,the information obtained by PiCCO often instruct clinical doctors to choose the optimal treatment.

Objective To investigate the value of central venous pressure (CVP) combined with visual left ventricular ejection fraction(LVEF) as an indicator of fluid responsiveness in patients with septic shock.Methods A retrospective analysis of 83 patients with septic shock receiving fluid challenge was conducted.The hemodynamic changes were evaluated with the pulse indicator continuous cardiac output (PiCCO) monitor,and all the patients were divided into two groups:the responded group (△CI％ ≥15％)and the unresponded group(△CI ＜ 15％),according to the change in CI(△CI％).Those patients were divided into several subgroups,including low CVP group (CVP ＜ 8 mmHg) and high CVP group (CVP ≥ 8 mmHg),low LVEF group(LVEF ＜ 50％) and high LVEF group(LVEF ≥ 50％),according to the initial value of CVP and LVEF.The changes in hemodynamic variables were compared before and after fluid challenge in each subgroup.The ability of CVP and visual LVEF was evaluated to predict fluid responsiveness with receiver operating characteristic curves.Results Fifty three (63.9％) patients responded to the fluid challenge,and lower CVP and higher LVEF patients were more frequency in responded group.The threshold value of 8 mmHg CVP for prediction of fluid responsiveness revealed the area under the curve (AUC) of 0.646 (P =0.219),and 50％ visual LVEF revealed AUC of 0.729 (P =0.023).CVP in combination with visual LVEF for prediction of fluid responsiveness showed an AUC of 0.817 (P =0.001) with a sensitivity of 76.3％ and a specificity of 88.2％.Conclusions Visual LVEF alone and combined with CVP can be used as an indicator of fluid responsiveness in patients with septic shock.

Objective To investigate the relationship between plasma concentration of B type natri uretic peptide (BNP) and the severity and prognosis of patients with acute spontaneous intracerebral hemorrhage (ICH).Methods Review of 86 cases of patients with spontaneous intracerebral hemorrhage analysis in our hospital Department of Emergency/Surgical Intensive Care Unit (ED/S1CU) were admitted within 6 hours of admission to collect blood samples,head CT,biochemical index,Glasgow Coma Scale (GCS) score and other clinical data,and detected within 6 hours after admission,the admission of third days and 7 days of plasma BNP concentration.The blood volume of cerebral hemorrhage was computed.The GCS was used to evaluate nerve function after admission.The survival of 28 days was observed.Results The concentration of BNP detected at 3 time points increased with the increase of the amount of bleeding in patients with acute cerebral hemorrhage and increased with the decrease of GCS score at admission (P ＜0.01).The BNP concentration was mild higher in the small amount of bleeding group than that of the control group (P =0.094),while that of the other two groups were significantly higher (P ＜ 0.01).Concentration of BNP detected within 6 hours of admission was positively correlated with cerebral hemorrhage (r =0.551).The a mount of BNP in the 6 hours after admission of the GCS ＞ 8 group was significantly higher than those of the control group (P ＜ 0.05),and the GCS ≤ 8 group was significantly higher than that of the control group and GCS ＞ 8 group (P ＜ 0.01).The BNP concentration was negatively correlated with GCS score at admission (r =-0.532).The 28-day mortality was predicted by BNP ＞ 168 pg/ml for 6 hours,AUC was 0.814,the sensitivity was 75.0％ and the specificity was 81.4％.Conclusions The concentration of BNP in patients with acute spontaneous intracerebral hemorrhage increased with the increase amount of bleeding and the decrease of GCS score at admission.The concentration of BNP in the 6 hours after admission was correlated with the severity and the prognosis of the disease,which can be used as the important reference indicators for evaluating severity and prognostic prediction.

Objective:To explore the model of first aid skills training based on competition.Method:The second-year residents who participated in the competition in 2021 ( n = 142) were selected. According to whether they attended BLS training in the first year, they were divided into group A ( n = 88) who attended BLS training and group B ( n = 54) who did not. Chi-square test, T test, Wilcoxon rank sum test and Logistic regression were used in our study. Results:There was no significant difference in gender and specialty between both groups (female, 62.5% vs. 68.5%, P= 0.466; TCM, 50% vs. 53.7%, P= 0.668), but the real resuscitation experience of group A was more than that of group B (40.9% vs. 9.3%, P= 0.000). The qualified rate of CPR and the compression score in group A was higher than that in group B [(81.8% vs. 61.1%, P = 0.006; (30±5) vs. (25 ±10), P= 0.001], including compression frequency, depth, rebound and compression/respiration rate (73.9% vs. 55.6%, P= 0.024; 88.6% vs. 70.4%, P= 0.006; 96.6% vs. 87%, P= 0.031). In the theoretical examination, the correct rates of electrocardiogram [(53.63±2.9)% vs. (50.44±2.57)%] and first aid medication [(57.38±3.55)%, P = 0.001] in the two groups were significantly lower than the qualified rate. After adjusting other factors, Logistic regression analysis showed that the CPR qualification rate in group A was 2.769 times higher than that in group B ( P= 0.015, 95% CI 1.215~6.311) Conclusions:The first aid skills training mode based on competition can objectively reflect first aid skills level of residents. We found that the quality of CPR skills was not related to gender, specialty and real CPR experiences but experience of BLS training was an independent influencing factor. And how to identify and manage arrhythmias and how to choose different emergency drugs are urgent emergency skills for residents to improve.